Uchida Hidetoshi, Nishio Miki, Omeki Yumi, Takeuchi Yuka, Nagata Rina, Oikawa Shota, Nagatani Arisa, Eryu Yoshihiko, Hata Tadayoshi, Yoshikawa Tetsushi
Department of Pediatrics, School of Medicine, Fujita Health University, Toyoake, Japan.
Graduate School of Health Sciences, Fujita Health University, Toyoake, Japan.
Pediatr Cardiol. 2016 Dec;37(8):1458-1464. doi: 10.1007/s00246-016-1457-9. Epub 2016 Aug 23.
In patients with a ventricular septal defect, left-to-right shunting increases the left ventricular preload. This pathological change affects myocardial depolarization and repolarization and has the potential to evoke arrhythmogenic substrates. We examined the effect of ventricular septal defects on myocardial repolarization by investigating the variability in the repolarization interval. This retrospective study included 19 patients (mean age, 1.8 ± 2.1 years) who underwent surgical closure (mean left-to-right shunt ratio, 2.60 ± 0.55) and 26 age-matched healthy controls from 2008 to 2015. Using preoperative electrocardiograms, we studied two electrocardiographic parameters (heart rate-corrected repolarization and variability of repolarization) and four repolarization intervals (QT, JT, J point to T peak [JTp], and T peak to T end [Tp-e] intervals). The variability index (VI) was calculated from the logarithm of the ratio of the repolarization parameter variance to heart rate variance. The various measures were compared between the patients and controls, and significant differences were found in the corrected QT, JTp, and Tp-e intervals (p < 0.05). The VI of the four intervals also showed significant differences (patients vs.
QTVI, -0.55 ± 0.61 vs. -1.10 ± 0.53; JTVI, -0.33 ± 0.60 vs. -0.86 ± 0.57; JTpVI, -0.15 ± 0.78 vs. -0.73 ± 0.56; Tp-eVI, 0.75 ± 0.70 vs. 0.11 ± 0.73, respectively; p < 0.05). No correlation was found between the QTVI and corrected QT interval using linear regression analysis. These repolarization characteristics provide not only electrophysiological indices but also a new index with which to assess the pathophysiology of congenital heart disease.
在室间隔缺损患者中，左向右分流会增加左心室前负荷。这种病理变化会影响心肌的去极化和复极化，并有可能引发致心律失常基质。我们通过研究复极化间期的变异性，来探讨室间隔缺损对心肌复极化的影响。这项回顾性研究纳入了2008年至2015年间接受手术闭合治疗的19例患者（平均年龄1.8±2.1岁，平均左向右分流比2.60±0.55）以及26例年龄匹配的健康对照者。利用术前心电图，我们研究了两个心电图参数（心率校正复极化和复极化变异性）以及四个复极化间期（QT、JT、J点至T波峰[JTp]和T波峰至T波终末[Tp - e]间期）。变异性指数（VI）由复极化参数方差与心率方差之比的对数计算得出。对患者和对照者的各项测量指标进行比较，发现校正QT、JTp和Tp - e间期存在显著差异（p<0.05）。四个间期的VI也显示出显著差异（患者与对照者相比：QTVI，-0.55±0.61对-1.10±0.53；JTVI，-0.33±0.60对-0.86±0.57；JTpVI，-0.15±0.78对-0.73±0.56；Tp - eVI，0.75±0.70对0.11±0.73，p<0.05）。使用线性回归分析未发现QTVI与校正QT间期之间存在相关性。这些复极化特征不仅提供了电生理指标，还为评估先天性心脏病的病理生理学提供了一个新指标。
